import time
while True:
    try:
        radius = float(input('输入圆的半径R: '))
        radius1 = float(input('输入圆的半径r: '))
        n = int(input("保留几位小数/100\n"))
        y =  round(3.1415926535897932384626433832795028841971693993751058209749445923078164062862089986280348253421170679,n)
        perimeter = 2 * y * radius
        area = y * radius * radius
        wynf = radius * radius * 1.14
        wfny = radius * radius *0.86
        txy = y * (radius*radius-radius1*radius1)
        perimeter1 = 2 * y * radius/4*3
        area1 = y * radius * radius/4*3
    except ValueError:
        print("找事是吧，输数子！")
    except:
        print("嗯？，别耍花招！")

    else:
        print('周长: %.2f' % perimeter)
        print('面积: %.2f' % area)
        print("外圆内方：%.2f" % wynf)
        print("外方内圆：%.2f" % wfny)
        print("同心圆：%.2f" % txy)
        print('周长4/3: %.2f' % perimeter)
        print('面积4/3: %.2f' % area)


